1. Technical Field
The present disclosure relates to a turbocharger including a valve that opens and closes a flow path which is opened to an internal space of a housing.
2. Description of the Related Art
Conventionally, there is known a turbocharger in which a rotation shaft where a turbine wheel is provided at one end and a compressor wheel is provided at the other end is rotatably held in a bearing housing. Such a turbocharger is connected to an engine, the turbine wheel is rotated by an exhaust gas discharged from the engine and the compressor wheel is rotated by the rotation of the turbine wheel via the rotation shaft. In this way, along with the rotation of compressor wheel, the turbocharger compresses air and feeds it out to the engine.
The turbocharger disclosed in Japanese Patent Laid-Open Publication (Translation of PCT Application) No. 2013-512373 (Patent Literature 1) includes a bypass flow path. The bypass flow path passes apart of an exhaust gas from a turbine housing to the downstream side of a turbine wheel not via a turbine scroll flow path communicating with the turbine wheel. Namely, the part of the exhaust gas passes through the bypass flow path to thereby bypass the turbine scroll flow path and the turbine wheel. The bypass flow path is opened and closed by a valve. The valve is provided within the turbine housing and is coupled to a shaft. The shaft is rotatably supported by a bearing portion provided in the turbine housing. The bearing portion is placed in the turbine housing so as to penetrate through the inside and outside of the turbine housing. As described above, when the shaft is rotated by the power of an actuator, the valve is operated together with the shaft, and thus the bypass flow path is opened and closed by the operation of the valve.